This gear fits the Canon FD 135mm f/3.5 Lens lens.

Focus gear designed specially for this lens and is compatible with any standard 0.8 Module follow focus. Focus gears is 3-6mm “high” off the focus ring of your lens for a clean, low profile gear that slides smoothly onto your lens and into your current lens case. The gears do not have to be removed after each use although you can if you like. Each gear comes with a lifetime of support.